Azo dyestuffs



liitented May 29, 1928 UNITED STATES PATENT OFFICE.

.rosnr when, or wmsnoit'r, GERMANY, ASSIGNOR' '10 ,GRASSELLI nn'zsru'rr con.-

PORATION, OF NEW YORK, N. Y.,

A CORPORATION OF DELAWARE.

[AZO DYESTUIFS.

No Drawing. Application filed June 23, 1027, Serial No. 201,028, and in Germany June 28, 1926.

I have found new and valuableazo dyestuffs which are obtainable by coupling a' diazotized amino-naphthol-ether with a 2.3- hydroxynaphthoic-acid arylid and which correspond to the general formula:

co-Nrr-m wherein R stands for a naphthalene residuesubstituted by at least one alkyloxy-group, and R, for an aryl-residu'e substituted or not. They are distinguished by clear violet shades light and Emample I.

2.5 parts by weight of the hydrochloride salt of the 7-methoxy-l-amino-naphthalene, a5 melting at 81 0., are dissolved in water and diazotized in the usual manner after the addition of 4 parts by weight of hydrochloric acid. In order to increase the stability of the diazo-compound, naphthalene-sulphonic acids such as 1.5. naphthalene-disulfonic acid may be admixed. Water is then added to increase to 1000 parts by volume. After havins neutralized the excess of mineral acid with sodium acetate, a cotton hank, previously treated with a solution containing 2.5 grams per litre of 2': 3-hydroxy-naphthoic a'cid-B-naphthali'ds .is introduced and agitated in thesolution for about minutes'.

After rinsing, the goods are soaped in boil ing water. A clear reddish violet is thus obtained possessing very good fastness to chlorine, boiling and light. The dyestuif probably has the following formula:

- OOH:

. I H i (JO-mm Ew ample I I 2.5 parts by Weightof the hydrochloride salt of the l-m'etho'xy-S-aminonaphthaline (Berichte der deutschen chemischen Gesellschaft, volume 39, page 3336) are dissolved in water and diazotiz'ed in the usual manner.

Water is then added to this solution in order to increase to 1000 parts by volume. After having neutralized the excess of inirieral acid with sodium carbonate, a cotton hank, previously treated with an alkaline solution containing 6 parts by weight ,B-hydroxynaphthoyl 2 amino 1, 4-hydroquinone-d1- methylether dissolved in 1000 parts by volume of water. is introduced to this diazo solution and agitated in this solution for about 20 minutes. After rinsing, the goods are soaped in boiling water. A red violet is thus'obtained possessing very good fastness to chlorine, to boiling and to light. When pre- Dared in substance this dyestufi represents a. Bordeaux dyed powder, soluble in concentrated sulfuric acid with a blue shade. The

dyes'tufi probably has the following formula:

HaCO

N=== N I OH OOH: coma-Q I claim:

1. As new products azo dyestufisof the general formula:

N-N-R 1 in which R stands for a naphthaline residue substituted by at least one alkyloxy-gr'oup, and R for an a l-residue substituted or not, which are in a ry state dark powders soluble in concentrated sulfuric acid with blue color and yielding clear violet shades of.

" excellent-fastness to chlorine, light and boil ing. 7

2. Asnew products azo dyestuffs of the general formula:

N-N-R comm-m in which R. is a naphthalene re sidue subcoloration and yielding clear violet shades scribed in claim 2.

my hand.

' cellent fastness to chlorine, light and boiling.

' 3. As a new product the am d estufl's of 40 the formula: y

which is in a dry state a, reddish violet powder dissolving in vsulfuric acid with a blue of excellent fastness to chlorine, to light and to-boiling.

4. Materials dyed with the dyestuffs described in claim 1. A

5. Materials dyed with the dyestufi's de- '6. Materials dyed with the dye stuff de scribed in claim 3.

In testimony whereof I have hereunto set J OSEF HALLER. 

